Method and means for skinning meat

ABSTRACT

A meat skinning machine of the type having a skin gripping roll and a concave shoe cooperating with a skinning blade and the gripping roll to pull the skin through the machine and part the skin from a piece of meat. A stripper roll is mounted adjacent the gripper roll to strip the skin from the gripper roll after the skin has been removed from the meat. The shoe and skinning blade are held concentrically with the gripping roll by air piston means. The air piston means are controlled by a photoelectric cell means which functions to instantaneously move the shoe and blade to the skinning position as soon as the meat approaches the close proximity of the blade. The instantaneous initial bite of the blade into the meat is enhanced and accelerated by pivoting the shoe above and forwardly of the point of engagement of the blade with the oncoming meat to be skinned. The method involves the holding of the shoe adjacent the gripping roll concentrically with sufficient force to grip the removed skin but with insufficient force to prevent puncture of the skin by the gripping roll. The method further holds the skin uniformly against the gripper roll, and then strips the skin from the gripper roll by a remotely located stripper roll to insure that a uniform thickness of skin is removed.

United States Patent 72 Inventor Ray T. Townsend Des Moines, Iowa [21]Appl. No. 706,941 (22] Filed Feb. 20, 1968 [45] Patented Feb. 2, 1971[73] Assignee Townsend Engineering Company Des Moines, Iowa acorporation of Iowa Continuation-impart of application Ser. No. 616,692,Feb. 16. 1967. now abandoned.

[54] METHOD AND MEANS FOR SKINNING MEAT 5 Claims, 12 Drawing Figs.

[52] U.S.Cl 146/130 [51] Int. Cl A22c 17/12 [50] Field of Search146/130. 241

[56] References Cited UNITED STATES PATENTS 2,539,692 1/1951 Hickman eta1 146/130 3,255,485 6/1966 Runnells, Jr. et al. 146/130X FOREIGNPATENTS 376,216 5/1964 Switzerland 146/130 HZL.

I 'l I I l I I l; I

Primary Examiner-Willie G. Abercrombie AltorneyZarley, Mc Kee & ThomteABSTRACT: A meat skinning machine of the type having a skin grippingroll and a concave shoe cooperating with a skinning blade and thegripping roll to pull the skin through the machine and part the skinfrom a piece of meat. A stripper roll is mounted adjacent the gripperroll to strip the skin from the gripper roll after the skin has beenremoved from the meat. The shoe and skinning blade are heldconcentrically with the gripping roll by air piston means. The airpiston means are controlled by a photoelectric cell means whichfunctions to instantaneously move the shoe and blade to the skinningposition as soon as the meat approaches the close proximity of theblade. The instantaneous initial bite of the blade into the meat isenhanced and accelerated by pivoting the shoe above and forwardly of thepoint of engagement of the blade with the oncoming meat to be skinned.The method involves the holding of the shoe adjacent the gripping rollconcentrically with sufficient force to grip the removed skin but withinsufficient force to prevent puncture of the skin by the gripping roll.The method further holds the skin uniformly against the gripper roll,and then strips the skin from the gripper roll by a remotely locatedstripper roll to insure that a uniform thickness of skin is removed.

PATENTED rm 219m SHEET 1 BF 5 CAW PATENTED FEB 2 I971 SHEET 2 BF 5 P W T7bwA/5EA/0 PATENTEU FEB 219w SHEEI h 0F 5 1 METHOD AND MEANS FORSKINNING MEAT This application is a continuation-in-part of copendingapplication Ser. No. 616,692 filed Feb. [6, 1967. now abandoned.

The principal object of this invention is to increase the yieldresulting from a skinned piece of meat. and this result is achieved byminimizing or eliminating the fat from the skin roller in which thestripping elements are mounted. It is therefore an object of thisinvention to provide a method and means of skinning meat which willremove skin from meat in substantially uniform layers and which willeliminate the above described ribbons of fat which are sometimes left onskins removed by prior art devices. More specifically, it is an objectof this invention to provide a method and means for skinning meatwherein the skin is uniformly supported on the gripping roll, and isremoved therefrom by a stripper roll remotely positioned with respect tothe gripper roll.

Prior skinning devices of the type mentioned heretofore have notprecisely controlled throughout the skinning operation the relativeconcentric positions of the gripping roll and the concave pressure shoeon which the blade is mounted, nor has the pressure between thesecomponents been carefully controlled. The results of these problems inthe prior art are that some defective skinning results, and theseparated skin is often mutilated or otherwise damaged by the gripperroll. Therefore, it is an object of this invention to provide a methodand means for skinning meat whereby the juxtaposition and pressurebetween the concave shoe and the gripping roll are carefully maintainedin a predetermined condition'throughout the skinning operation toseparate a uniform layer of skin and to avoid damage to the skin as itis removed.

A further problem of prior art skinning devices is the limited number ofpieces of meat that can be skinned in a given period of time. In somemachines, the skinning cycle is manually controlled, and in others theskinning machine is set to cycle only a given number of times during afixed period of time. It is therefore a further object of this inventionto provide a method and means for skinning meat that can greatlyaccelerate the number of pieces of meat that can be skinned in a givenperiod. In this same connection, it is a still further object of thisinvention to provide a method and means for skinning meat that willpermit the skinning blade to quickly be moved to a cutting position sothat an excess of fat will not be left on the edge of the skin initiallycut from the meat. More specifically, the forward pivotal position ofthe arm-supported pressure shoe upon which the skinning blade is mountedpermits the blade to more quickly and more effectively make its initialbite into the meat. A photoelectric cell or switch, which are actuatedby the meat as it moves into the cutting zone, instantaneously bring thepressure shoe and the skinning blade into the skinning position.

A still further object of this invention is to provide serrations on thestripper roll in the form of teeth which slant forwardly with respect tothe direction of rotation of the stripper roll in order to moveeffectively, disengage the skin from the skin gripping roll, and also tocarry it away from the skin gripping roll without clogging the skingripping surface thereof.

An additional object of this invention is to provide a strippermechanism for a skinning machine which is easy to clean and keep in asanitary condition as required for machines of the general characterherein disclosed.

A still further object of this invention is to provide a skinningmachine which is economical of manufacture, durable in use, and refinedin appearance.

These and other objects will be apparent to those skilled in the art.

This invention consists in the construction, arrangements, andcombination, of the various parts of the device, whereby the objectscontemplated are attained as hereinafter more fully set forth,specifically pointed out in the claims, and illustrated in theaccompanying drawings, in which:

FIG. 1 is a plan view of the skinning machine of this invention;

FIG. 2 is a rear elevation thereof of the discharge side of the machinewith certain parts being broken away to more fully illustrate itsconstruction;

FIG. 3 is a side elevation thereof with a portion of the housing beingbroken away to more fully show its construction;

FIG. 4 is a side elevation view similar to that of FIG. 3 but viewedfrom the opposite side of the machine;

FIG. 5 is an enlarged scale sectional view taken on line 5-5 of FIG. 2;

FIG. 6 is a partial sectional view similar to that of FIG. 5 but showsthe components as a piece of meat is approaching the cutting zone;

FIG. 7 is a partial sectional view similar to that of FIG. 6 but showsthe blade making its initial cut into the meat;

FIG. 8 is a partial sectional view similar to that of FIG. 6 but showsthe operating position of the components during the skinning operation;

FIG. 9 is a partial perspective view of the shoe assembly;

FIG. 10 is a sectional view of the stop for the shoe assembly taken online 10-10 of FIG. 9;

FIG. 11 is a schematic view of the power control system for the shoeassembly; and

FIG. 12 is a plan view of an electrical pressure responsive switch whichcan be used in lieu of the photoelectric cell for purposes ofcontrolling the action of the shoe assembly.

Frame 10 (FIG. 3) is supported on pedestal l2, and housing 14 offiberglass or the like is secured to frame 14 in any convenient manner.Electric motor 16 is secured to frame 10 and has power output shaft 18with pulley 20 rigidly secured thereto. Belt 22 connects pulley 20 todrive pulley 24 which is mounted on shaft 26. Shaft 26 is joumaled byconventional bearings (not shown) on frame 10.- Drive gear 28 is rigidwith shaft 26 and is operatively connected by chain 31 to a like gear 30on the end of shaft 32. Shaft 32 is joumaled by any conventional bearingmeans on frame 10. Gear 30 is rigidly secured to the end of gripper roll34.

With reference to FlG. 4, gear 36 is also fixed to shaft 26 and is inoperative engagement with like gears 38 and 40 on the ends of drive roll42 and skin stripping roll 44, respectively. Each of the rolls 42 and 44are rotatably joumaled in suitable bearings within housing 14. Driveroll 42 is a part of conveyor 46 which includes idler roll 48 and belt50. Chain 52 effects the operative connection between gears 36, 38 and40.

Gear 54 is rotatably mounted within housing 14 and is in mesh with chain52 (FIG. 4). A drive gear 56 is rigidly secured thereto and isoperatively connected by chain 57 to gear 58 on shaft 60, which in turnis rotatably mounted on frame 10 by any convenient means. Gear 62 isrigid with gear 58 and is operatively connected by chain 64 to a gear onthe shaft of pneumatic hold down roller 66. The holddown roller 66 ismade and functions in accordance with Pat. No. 2,722,255 issued Nov. 1,I955.

Shoe assembly 68 (FIG. 9) includes a pressure shoe 70 mounted onforwardly and upwardly extending arms 72. As shown in FIGS. 58, shoe 70has a concave circular surface 74 below and rearwardly of skinning blade76. Adjusting screws 78 (FIG. 5) are provided in shoe 70 for adjustingthe position of skinning blade 76. Shoe assembly 68 is rotatably securedto frame 10 forwardly and above the cutting edge of blade 76 by pins 80which are secured to forward ends of arms 72. As will be discussedhereafter, the pivotal location of arms 72 greatly enhances the initialbite of the blade 76 into the oncoming meat.

A pair of vertically disposed air cylinders 82 are secured to therearward portion of frame 10 (FIGS. 2 and 5), and a piston rod 84 with apiston 86 on the lower end thereof extends upwardly and outwardlytherefrom through grommets 88 to a pivotal connection 90 with the bottomof shoe 70. Springs 92 extend between the tops of cylinders 82 tonormally urge the piston rod upwardly. Cooperating shoulders at 96 onthe cylinders 82 and piston rods 84 limit the upper movement of therods. When the pistons 86 are in the "upper" position of FIG. 5. theshoe 70 and shoe assembly 68 are in their upper or nonoperatingpositions.

The pistons 86 can be moved to a lower position in cylinders 82 byintroducing compressed air into the upper ends of the cylinders. Thisphenomenon will cause the shoe assembly 68 to pivot about pins 80 sothat the shoe will move from the positions of FIGS. 5 and 6 towards theultimate operating position in FIG. 8. Air lines 98 connect the upperends of cylinders 82 to a solenoid-controlled air valve 100 (FIG. 2).which in turn is connected to a source of compressed air 102 (FIG. 11).The solenoid of valve 100 is connected to a conventional photoelectriccell 104 (FIG. 5) which ispositioned laterally and slightly forwardly ofthe skinning blade 76. Air valve 100 is normally closed andphotoelectric cell 104 normally has its contact points in an opencondition. A source of light such as bulb 106 is mounted laterallydirectly across from photoelectric cell 104, and the contact points ofthe cell remain open until the beam of light from bulb 106 is broken.The breaking of the beam of light by a piece of meat will permitphotoelectric cell 104 to close. whereupon the solenoid of valve 100will open the valve to provide air to cylinders 82. Valve 100 has anexhaust port to relieve the cylinders of compressed air when the valveis open, so that the springs 92 can move the pistons upwardly whenevervalve 100 opens.

The downward movement of shoe assembly 68 is limited by adjustable cams108 (FIGS. 5 and on arms 72 thereof which engage stop elements 110 onhousing 14. Cams 108 can be rotated to adjust the degree of downwardmovement of the shoe assembly. With reference to FIG. 8, the concavesurface 74 of shoe 70 is separated a few thousandths of an inch from theteeth of gripping roll 48, and the curvature of the concave surface 74is concentric with the outer periphery of the teeth.

With reference to FIGS. 2 and 5. it is noted that the gripping surfaceof roll 48 is comprised of a plurality of continuous longitudinal teethor serrations 112 which slant in the direction of the roll. Theseserrations are not intermittently interrupted along their length byobjectionable finger stripping grooves as were the rolls in theaforementioned patents. and as a consequence, the skin is more uniformlysupported on the serrations or teeth, and no residue ribbons of fat areleft on the skin.

With respect to the skin engaging surface of the stripper roll 50, it islikewise provided with continuous elongated serrations or teeth 114which slant in the direction of rotation. These teeth may also belongitudinally arranged but are preferably spirally arranged as shown inFIG. 2. The spiral configuration of teeth 114 is superior in that aself-cleaning action is produced by a tendency to auger anything thatdoes stick to the teeth endwise along the roll, and the materialaccumulates at the end thereof and finally drops off without thenecessity of a manual cleaning operation being required.

With reference to FIG. 11, lines 116 and 118 extend from photoelectriccell 104 from a source of electrical power. Bulb 106 is connected acrossthese lines as is motor 16. Switch 120 is imposed in line I16 to controlthe machine.

A conventional pressure responsive electrical switch 122 (FIG. 12) maybe substituted for photoelectric cell 104, in which case bulb 106 wouldalso be eliminated. Switch 122 would assume the same position as cellI04, and would control valve 100 in the same manner as did cell 104.

The normal operation of the device of this invention is as follows: Thecams 108 are set to provide a few thousandths of an inch clearancebetween the concave surface 74 of shoe 70 and the outer periphery ofteeth [12 on gripper roll 34 when the shoe assembly 68 is in its loweroperating position (FIG. 8). When switch 120 is closed. motor 16 isstarted and bulb 16 is lighted to maintain the contacts of photoelectriccell 104 is an open position. This leaves solenoid air switch I00 in itsnormally closed condition to keep compressed air out of cylinders 82.whereupon the springs 92 function in the manner described to push theshoe assembly 68 to its upper position (FIGS. 5 and 6). The power trainpreviously described will cause the holddown roller 66. the conveyorbelt 50, the gripper roll 34. and the stripping roll 44 to rotate in thedirection of the arrows indicated in FIG. 5. The stripper roll 44rotates at a faster speed than gripper roll 34. It is important to notethat the gripper .roll 34 and stripping roll 44 rotate in the samedirection, with the stripping roll being separated from the grippingroll a few thousandths of an inch and being positioned beneath andslightly rearwardly'of the gripper roll.

Slabs of meat M with a layer of skin 8 are deposited (usually in rapidsequence) on belt 50, and are engaged and stabilized by the holddownroller 66 (FIG. 6) as the meat approaches the cutting zone. Thecontinued rearward movement of the meat brings the skin S on the lowersurface thereof into initial contact with the teeth 112 on gripping roll34. Because the teeth are longitudinally continuous, the meat and skinthereof are held in a straight longitudinal plane which was not possibleon earlier machines in the art wherein the gripping roll had a pluralityof annular grooves on its surface to accommodate stripping elements,which permitted some slumping of the meat and skin into these grooves.

The instant that the meat breaks the beam of light from bulb 106, (oraetuates pressure switch 122 if such is used in lieu of photoelectriccell 104), the photoelectric cell 104 functions in the manner previouslydescribed, whereupon air is provided to cylinders 82 by valve to lowerthe shoe assembly 68 to the position of FIG. 8. The instantaneousreaction of the shoe assembly 68 to the oncoming meat is highlyimportant, because it permits blade 76 to make an instantaneous biteinto the meat which substantially reduces the residue of fat on theleading edge of the separated skin as the blade 76 seeks out thethickness of the skin. Because of the inoperative position of the bladein FIG. 6 is substantially above the gripping roll 34 a distance greaterthan the thickness of skin S, it will be appreciated that considerablefat would be left on the first portion of separated skin if the shoe 70and blade 76 were permitted anything other than an instant to move tothe ultimate skinning position of FIG. The position of the shoe 70 andblade 76 in FIG. 7 depicts the initial entry of the blade 76 into themeat in that fractional second as the shoe 70 moves from the position ofFIG. 6 to that of FIG. 8.

Two other highly important phenomena come into play during this sameinstant that the shoe assembly is moved into its skinning position. Thearms 72 on shoe assembly 68 have been carefully pivoted forwardly andslightly above the cutting zone defined by the cutting edge of blade 76.It has been determined that the geometrical relationship between thecutting edge of the downwardly beveled blade 76 and the pivotal axis ofthe arms 72 permits a vastly superior initial penetration of the meat bythe blade, than if the arms 72 were pivoted elsewhere, particularly at apoint rearwardly rather than forwardly as determined by the location ofpins 80.

A second phenomenon that is highly important is that the concave surface74 of shoe 70 is held in a position concentric with the periphery of theteeth 112 on gripping roll 34, and this uniform spacing of the surface74 with respect to the teeth achieves a beneficial result when thisposition is maintained throughout the skinning operation. Not the leastof these advantages is that the skin is held against the teeth of thegripping roll with uniform pressure, with no excess pressure beingapplied thereto particularly in the area of blade 76. As a consequence,the skin is not penetrated by the teeth 112 of gripping roll 34, and theskin can then be used for more profitable purposes such as leatherrather than for less profitable uses such as gelatin. The concavesurfaces of the shoes of the previously patented machines were not heldas a matter of course in the above-described concentric relationshipwith the teeth of the gripping roller throughout the duration of theskinning operation. The precise operating position of the shoes of theseearlier machines during the skinning operation was either determined bythe tolerances of the treadlcs or the reaction ability of the machineoperator. and in many instances the machines were dowelled to hold thebottom of the shoe further away from the gripping roll than the top ofthe shoe so as to concentrate pressure on the skin in the area of theblade. The present method of controlling and positioning the shoe 70achieves more efficient skinning results, and the separated skin is notperforated or mutilated in the manner of the prior machines.

By providing a stripping roll remote from the gripping roller. theentire longitudinal length of the teeth 112 on gripping roll 34 can beused to support the skin to achieve the superior yield discussedheretofore. The skin 5 follows the gripper roll 34 until-the lower edgeof the skin engages the teeth of stripper roll 44, whereupon the skin isreversed in direction and pulled away from the roll 14 as illustrated.Soon after the initial engagement of the skin with the stripper roll theincreased surface speed of the stripper roll tends to pull the skin tothe solid-line bridging position shown and away from the skinning rollthereby efficiently stripping the skin from the skinning roll anddisposing of it as far as the skinning machine is concerned. The skinsmay drop into a container or may be delivered to a chute, conveyor orthe like.

Thus, from the foregoing, it is seen that this invention will accomplishat least all of its stated objectives.

lclaim:

1. In a meat skinning machine having forward and rearward ends:

a laterally extending gripping roll;

a blade means positioned adjacent said gripping roll;

means for rotating said gripping roll whereby a layer of meat can bemoved rearwardly towards said blade means to separate a layer of skinfrom said meat;

arm means extending forwardly from said blade means and being pivotallymounted forwardly of said blade means and said gripping roll, wherebysaid arms can be pivoted in one direction to move said blade means to aninoperative position away from said gripping roll, and said arms can berotated in a second direction to move said blade means to an operativecutting position adjacent said gripping roll;

a power means to selectively pivot said arm means and said blade meansto move said blade means to said operative and inoperative positions;and

means responsive to the movement of meat towards said blade means beingoperatively connected to said power means whereby said power means willmove said blade means to said operative cutting position when actuatedby meat moving towards said blade means.

2. The skinning machine of claim 1 wherein means responsive to themovement of meat includes a light source and a photoelectric cellpositioned on opposite sides of the path of travel of said meat.

3. The skinning machine of claim I wherein the means responsive to themovement of meat includes a pressure responsive electrical switchpositioned adjacent the path of travel of said meat.

4. In a meat skinning machine having forward and rearward ends:

a laterally extending gripping roll;

a blade means positioned adjacent said gripping roll;

means for rotating said gripping roll whereby a layer of meat can bemoved rearwardly towards said blade means to separate a layer of skinfrom said meat;

arm means extending forwardly from said blade means and being pivotallymounted forwardly of said blade means and said gripping roll. wherebysaid arms can be pivoted in one direction to move said blade means to aninoperative position away from said gripping roll, and said arms can berotated in a second direction to move said blade means to an operativecutting position adjacent said gripping roll;

a power means to selectively pivot said arm means and said blade meansto move said blade means to said operative and inoperative positions;and

said power means including a cylinder and reciprocating piston assemblyoperatively connected to said blade means whereby reciprocation of saidpiston assembly will move said blade means to and from its inoperativeand operative positions.

5. in a meat skinning machine having forward and rearward ends, alaterally extending gripping roll:

a blade means positioned adjacent said gripping roll;

means for rotating said gripping roll whereby a layer of meat can bemoved rearwardly towards said blade means to separate a layer of skinfrom said meat;

arm means extending forwardly from said blade means and being pivotallymounted forwardly of said blade means and said gripping roll, wherebysaid arms can be pivoted in one direction to move said blade means to aninoperative position away from said gripping roll, and said arms can berotated in a second direction to move said blade means to an operativecutting position adjacent said gripping roll;

an automatic power means operatively connected to said arm means topivot said arm means and said blade means to move said blade means tosaid operative and inoperative positions; and

means responsive to the movement of meat towards said blade meansoperatively connected to said power means whereby said power means willmove said blade means to said operative cutting position when actuatedby meat moving towards said blade means.

1. In a meat skinning machine having forward and rearward ends: alaterally extending gripping roll; a blade means positioned adjacentsaid gripping roll; means for rotating said gripping roll whereby alayer of meat can be moved rearwardly towards said blade means toseparate a layer of skin from said meat; arm means extending forwardlyfrom said blade means and being pivotally mounted forwardly of saidblade means and said gripping roll, whereby said arms can be pivoted inone direction to move said blade means to an inoperative position awayfrom said gripping roll, and said arms can be rotated in a seconddirection to move said blade means to an operative cutting positionadjacent said gripping roll; a power means to selectively pivot said armmeans and said blade means to move said blade means to said operativeand inoperative positions; and means responsive to the movement of meattowards said blade means being operatively connected to said power meanswhereby said power means will move said blade means to said operativecutting position when actuated by meat moving towards said blade means.2. The skinning machine of claim 1 wherein means responsive to themovement of meat includes a light source and a photoelectric cellpositioned on opposite sides of the path of travel of said meat.
 3. Theskinning machine of claim 1 wherein the means responsive to the movementof meat includes a pressure responsive electrical switch positionedadjacent the path of travel of said meat.
 4. In a meat skinning machinehaving forward and rearward ends: a laterally extending gripping roll; ablade means positioned adjacent said gripping roll; means for rotatingsaid gripping roll whereby a layer of meat can be moved rearwardlytowards said blade means to separate a layer of skin from said meat; armmeans extending forwardly from said blade means and being pivotallymounted forwardly of said blade means and said gripping roll, wherebysaid arms can be pivoted in one direction to move said blade means to aninoperative position away from said gripping roll, and said arms can berotated in a second direction to move said blade means to an operativecutting position adjacent said gripping roll; a power means toselectively pivot said arm means and said blade means to move said blademeans to said operative and inoperative positions; and said power meansincluding a cylinder and reciprocating piston assembly operativelyconnected to said blade means whereby reciprocation of said pistonassembly will move said blade means to and from its inoperative andoperative positions.
 5. In a meat skinning machine having forward andrearward ends, a laterally extending gripping roll: a blade meanspositioned adjacent said gripping roll; means for rotating said grippingroll whereby a layer of meat can be moved rearwardly towards said blademeans to separate a layer of skin from said meat; arm means extendingforwardly from said blade means and being pivotally mounted forwardly ofsaid blade means and said gripping roll, whereby said arms can bepivoted in one direction to move said blade means to an inoperativeposition away from said gripping roll, and said arms can be rotated in asecond direction to move said blade means to an operative cuttingposition adjacent said gripping roll; an automatic power meansoperatively connected to said arm means to pivot said arm means and saidblade means to move said blade means to said operative and inoperativepositions; and means responsive to the movement of meat towards saidblade means operatively connected to said power means whereby said powermeans will move said blade means to said operative cutting position whenactuated by meat moving towards said blade means.